Valve for heaters



United States Patent 2,781,780 Patented Feb. 19, 1957 fltice VALVE FOR HEATERS Jerome G. Zahradka, Cicero, Ill., assignor to Motorola, Inc., Chicago, 11]., a corporation of Illinois Application August 19, 1952, Serial No. 395,120

1 Claim. (Cl. 137--608) The present invention relates to air heaters of the type consuming liquid fuel such as gasoline or kerosene, and more particularly to an improved fuel supply system for use in such heaters.

Liquid fuel burning heaters are known in which the liquid fuel is vaporized andmixed with air in a conditioning chamber prior to ignition and application to the combustion chamber of the heater. A combustible mixture is formed in the conditioning chamber which is supplied to burner ports adjacent the combustion chamher at which it is ignited and burned. Such an arrange ment has proved advantageous since its power requirement is low, its efliciency is high and the necessary equipment is relatively simple, compact and inexpensive.

Copending application Serial No. 52,169, filed October 1, 1948, in the name of Stanley J. Budlane, entitled Heater, and assigned to the present assignee, which issued March 30, 1954, as Patent 2,673,558, discloses and claims a heater utilizing the above described vaporizing principles of fuel conditioning. The Budlane arrangement utilizes a fuel vaporizing block having an igniter flame directing passage, a pilot burner passage, and two main burner passages extending therethrough. The pilot and main burner passages terminate respectively in burner ports at the front of the vaporizing block, and the igniter flame directing passage terminates in a port at the front of the block adjacent the pilot burner port. An igniter unit is supported at the back of the block in communication with the flame directing passage. sure is supplied continuously to the igniter unit and to the pilot and main burner passages, whereas the liquid fuel is selectively applied to the igniter and to the pilot and main burner passages. To initiate the heating process, liquid fuel is first supplied to the igniter wherein it is heated by an electrical element and mixed with air to form a combustible mixture which is ignited to produce a flame in the flame directing passage. This flame initially heats the vaporizing block and fuel is then supplied to the pilot burner passage wherein it is vaporized and mixed with air to form a combustible mixture which is ignited at the pilot burner port by the igniter flame. The resulting pilot flame heats the vaporizing block to the operating temperature, and one or both of the main burners may be brought into operation by a selective application of fuel to the main burner passages. Such application of fuel to the main burner passages results in a combustible mixture at the main burner ports which is ignited by the pilot flame.

The fuel supply system utilized in the Budlane application, comprises a fuel pump for drawing liquid fuel such as kerosene or gasoline from a fuel tank, and a fuel metering unit for receiving the fuel from the pump. The fuel metering unit is electrically operated to supply fuel selectively to the igniter unit and to the pilot and main burner passages-in the vaporizing block to initiate and maintain the operation described above.

The present invention is concerned with a fuel supply system which may be utilized in the previously described Air under pres- I Budlane heater, and which is constructed in a new and improved manner to supply fuel selectively to the various elements and passages of the heater.

It is, accordingly, an object of this invention to provide a new and improved fuel supply system for selectively supplying liquid fuel to the various units and passages of a fuel burning air heater unit.

A further object of the invention is to provide such a new and improved fuel supply system that utilizes a minimum of component parts and yet which operates with a righ degree of efliciency to perform its intended purpose.

Yet another object of the invention is to provide such a new and improved fuel supply system that may be constructed in a simple and expeditious manner and which therefore constitutes a relatively inexpensive structure.

A still further object of the invention is to provide such an improved fuel supply system that is extremely rugged in construction and which may operate over long;

periods of time with a minimum of servicing.

The features of this invention which are believed to be new are set forth with particularity in the appended which Fig. 1 shows a top view of a heater unit which may incorporate the fuel supply system of this invention; and

Figs. 2-7 are various views of a fuel metering unit utilized in the fuel supply system of this invention and constructed in accordance with the invention.

The fuel metering component of the fuel supply system of this invention comprises a base plate having a fuel inlet passage extending therein and communicating with its upper surface. A series of fuel outlet orifice units are positioned in the base plate and extend therethrough and project above its upper surface. A fuel guiding gasket is supported on the base plate and has a thickness greater than the projecting portions of the orifice units, and the gasket also has a series of apertures embracing the projecting portions of the orifice unit With slots interconnecting the apertures, the gasket forming in conjunction with the base plate a fuel container in communication with the fuel inlet passage. A flexible diaphragm covers the gasket and is normally spaced from the upper extremities of the orifice units so that fuel may flow unimpeded from the container out through the orifice unit. A series of plungers are supported above the diaphragm in respective axial alignment with the orifice units, and means are provided for reciprocating the plungers to seat the diaphragm selectively on the upper extremities of the orifice unit and arrest the fuel flow therethrough.

The heater unit of Fig. 1 comprises a housing 3.4 within which the various operating members are enclosed. A burner assembly is enclosed within a casing 64 which is coupled to heat exchanger 65. Fuel is supplied to the burner through the metering unit including solenoids 52 to 55 inclusive, which selectively supply fuel to the pilot burner and/or a plurality of main burners. An igniter 30 is provided for vaporizing fuel in the pilot burner. Fuel is fed to the metering unit by fuel pump 56, which is connected through pressure regulator 62 to line 63 (Fig. 4) into the metering unit. The fuel pump is connected by line 57 through filter 58 to line 59 which extends to the fuel tank. A surge chamber 64 is connected to the filter 55. The pump 56 is driven by a solenoid 160 having contacts for selectively energizing the same, with the contacts being bridged by condenser to prevent arcing thereacross.

Means for circulating air over the heat exchanger may be provided as disclosed and claimed in Patent 2,720,876

3 which issued October 18, 195 5 to Salners et al. The specific construction of the burner assembly for the heater is shown more specifically in Patent 2,733,757 issued February 7, 1 956 to Carlo et al.

Details of the fuel metering unit are shown in Figs 2-7. The unit comprises base plate 50 which is horizontally mounted on plate 35' and has a plurality of orifice units 69-72 extending therethrough in respective communication with the wells 36-39 and projecting above the upper surface of the base. A fuel guiding gasket 73 is supported on base plate 50 and has a thickness greater than the projecting portions of orifice units 69-72. Gasket 73 has a series of apertures 74-77 embracing the projecting portions of the orifice units, and the apertures are interconnected by slots 78-80, the apertures and slots in gasket '73 forming a fuel container in conjunction with base plate 50. The base plate has a passageway 81 therein, which communicates with fuel line 63 and terminates in the upper surface of the base plate within the aforementioned fuel container. is supported on gasket 73 and has apertures 33-36 aligned with apertures 74-77 in gasket 73 but of a somewhat smaller diameter. A rubber diaphragm 37 is supported over the shim and is normally spaced from the upper extremities of orifice units 69-72 so that fuel from the container may flow unimpeded through the orifice units.

A series of plungers 38-91 are supported in solenoid units 52-55 above the diaphragm 87 and in respective axial alignment with orifice units 69-72. are urged downwardly by respective coil springs 92-95 and seat diaphragm 87 on the upper extremities of the orifice units and arrest the fuel flow through the orifice units. Each of the plungers has a solenoid 96 associated therewith which, when energized, draws the corresponding plunger upwardly against the tension of its associated spring so that diaphragm 87 no longer bears against the upper extremity of the corresponding orifice unit so that fuel freely flows through the unit to the corresponding component or passage of the burner assembly.

Therefore, selective energization of solenoid units 52-55 causes a corresponding selective application of liquid fuel to the various orifice units 69-72 and, through the associated fuel lines, to the various components of the heater assembly. Copper shim 82 is interposed between diaphragm 87 and gasket 73 to prevent sagging of the diaphragm into the apertures and slots in the gasket after the meter unit has been in operation for an ap preciable time.

The invention provides therefore an improved fuel supply assembly which includes an electrically operated fuel metering unit constructed in an improved and simplified fashion to supply fuel selectively to the various passages and components of the heater; and which also includes an improved electrically operated fuel pump suction capable of operating over long periods of time with a minimum of attention.

While a particular embodiment of the invention has been shown and described, modifications may be made,

A copper shim 82 The plungers .4 and it is intended in the appended claim to cover all such modifications as fall within the spirit and scope of the invention.

I claim:

A fuel metering device for a heater unit and the like including in combination, a base plate having an essentially flat uni-planar upper surface and further having a fuel inlet passage extending therethrough and communicating with such upper surface, a series of fuel outlet orifice units dsposed in said base plate and extending li l'Cl'fTiiiTOUgil from the upper surface to the lower surface thereof, said orifice units having portions projecting upwardly beyond said upper surface of said base plate, a fuel-guiding gasket supported on said upper surface of said base plate and having a thickness greater than the projecting portions of said orifices and having a series of apertures embracing respective ones of said projecting portions and further having respective slots interconnccting such apertures so as to form a fuel container in comnunication with said fuel inlet passage, a thin metallic sheet supportedon said gasket and having apertures respectively aligned with the apertures in said gasket, a flexible rubber diaphragm supported on said metallic sheet and spaced thereby from the respective upper, extremities of said orifice units so that fuel may flow unimpeded from said fuel container through said orifice units, an upper plate secured to said base plate for holding the operating elements of the fuel metering device in an assembled condition, a series of plungers supported by said upper plate in respective axial alignment with said orifice units, respective spring biasing means for urging said plungers downwardly against said diaphragm to seat said diaphragm against said upper extremities of said orifice units and arrest the fuel flow through such units, and a plurality of independently operable solenoid units associated with respective ones of said plungers selectively to move said plungers against said spring biasing means to unseat said diaphragms selectively from said upper extremities of said orifice units and permit the flow of fuel through selected ones of said orifice units.

References Cited in the file of this patent UNITED STATES PATENTS 602,737 Farrell Apr. 19, 1898 766,420 Calley Aug. 2, 1904 2,109,814 Balfe Mar. 1, 1938 2,293,684 Holthouse Aug. 18, 1942 2,348,827 Lambert May 16, 1944 2,461,501 Miller Feb. 8, 1949 2,476,310 L'angdon July 19, 1949 2,544,347 Nicholson Mar. 6, 1951 2,587,356 McPherson Feb. 26, 1952 2,588,349 Dusek et al Mar. 11, 1952 2,595,311 Strange May 6, 1952 2,613,082 Guild Oct. 7, 1952 2,637,377 Budlane' May 5, 1953 2,677,390 Davis May 4, 1954 

